Sony PCG-XG29 - Manual (Page 68)

VAIO® Notebook User Guide #$
2
Remove the weight saver, and then pull out the battery pack.
3
Reinsert the weight saver.
✍
If you attach two battery packs, you can remove either of them without shutting down the
computer. When removing one battery pack, make sure that the other battery pack’s indicator
is on. If the indicator of the battery pack you are going to remove is on, right-click in the
task tray and switch it in the “Select the battery pack in use” window.